1.先把4个配置文件导入src下

2.把hadoop的4类jar包导入

3.如果使用java调试跑hadoop数据
需要注意权限！

public static void main(String[] args) throws Exception {

		System.setProperty("HADOOP_USER_NAME", "root");  //设置权限
		Configuration conf = new Configuration();
		conf.set("mapreduce.framework.name", "yarn");
		conf.set("yarn.resourcemanager.address", "master:8032");
		Job job = new Job();
		
		job.setJarByClass(MtMain.class);
		job.setMapperClass(MtMapper.class);
		job.setReducerClass(MtReduce.class);//设置三个class
		job.setJobName("Mt.jar");
		FileInputFormat.addInputPath(job, new Path("hdfs://master:9000/input/ncdc/"));
		FileOutputFormat.setOutputPath(job, new Path("hdfs://master:9000/output/ncdc"));
		job.setOutputKeyClass(Text.class);
		job.setOutputValueClass(IntWritable.class);
		System.exit(job.waitForCompletion(true)?0:1);
	}

4.并且把项目导出生成jar